Mechanically operated slip type elevator



May 16, 1933. F. J. YOUNG El AL 1,909,601

HECHANICALLY OPERATED SLIP TYPE ELEVATOR Filed March 29, 1927 2 Sheets-Sheet 1 May 16, 1933. F, YO N H A. 1,909,601

MECHANICALLY OPERATED SLIP TYPE ELEVATOR Filed larch 29, 1927 2 Sheets-Sheet 2 l E g Patented May 1 1933 UNITED STATES PATENT OFFICE FORREST J. YOUNG, OF TOBRANOE, AND JOSEPH A; DUNN, OF SOUTH PASADENA, GALI- IOBNIA, ASSIGNORS, BY MESNE ASSIGNMENTS, TO THE NATIONAL SUPPLY GOM- PANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO WICALLY OPERATED BLIP TYPE ELEVATOR Application filed March 29, 1927. Serial in. 179,219.

employed for the hoisting or lowering of o1l well casings during setting of the same or during the process of drilling wells, but

these elevators have for the most part empltayed slips which were manually operated an which required the use of sledges in many cases to remove the same from en gagement with the periphery of the casing when it was desired to move' the elevator from one section of casing to the other.

It is therefore an ob'ect of this invention to provide a mechanically operated slip type elevator which is adapted for use in the hoisting or lowering of oil well casings and which elevator includes a bod in which a plurality of slips are mounted to move inwardly toward the casing on mechanical actuation of a cam race ring which is rotatably mounted on the body to move the Slips inwardly into position to engage the casing and in which. elevator means are provided for preventing rotary movement of the slips during the actuation thereof.

Another object of this invention is to provide a mechanically operated slip type elevator including a body having a tapered bore within which a plurality of slips are mounted and adapted to be mechanically actuated, these slips and body having a plurality of interlocking lugs and recesses which provide riding surfaces.

Another object of this invention is to provide a mechanically operated slip elevator including a body in which a plurality of slips are mounted and adapted to be mechanically actuated, the slips and body having a plurality of interlocking sections. one of which sec ions on the body projects inwardly beyond the others to provide a riding surface on engagement of which the slips must ride outwardly away from the pipe within the body.

Another object of this invention is to proyide a mechanically operated slip elevator including a body having a plurality of slips mounted therein, which SllPS are provided with a crown radius less than the radius of the inner bore of the body so that the slips Wlll engage the body on a line contact at the crown of the same to permit the slips to be rocked in the body when in engagement with the pipeor casing.

In thedrawings:

Figure 1 is an elevation of a mechanically operated slip type elevator embodying this invention.

Figure 2 is a top plan view thereof partly broken away.

Figure 3 is a vertical section taken substantially on the line 3 -3 of Fig. 2, illustrating the slips in' the contracted or gripping position.

Figure 4 is a sectional view similar to Fig. 3. illustrating 'the slips as moved to the non-gripping position.

Figure 5 is a fragmental section illustrating the manner of mounting the guide blocks intermediate the mechanically operated slips.

Figure 6 is a top plan view partly in section of a cam race block embodied in this invention.

Figure 7 is a sectional elevation taken substantially on the line 7-7 of Fig. 6.

Figure 8 is a diagrammatic fragmental view illustrating one slip as mounted within a fragment of the body of the slip elevator and illustrating the slip as in engagement at a line contact with the body of the elevator.

In the preferred embodiment of this invention, the mechanically operated slip type elevator is illustrated as comprising a body 1, upon diametrically opposed points of which trunnions 2 are formed. Pivotally mounted on the trunnions Q is a bail 3 which is held in position by means of stud bolts 4 which are screw-threaded into the trunnions 2. Between the heads of thebolts 4 and surface of the eyes of the bails 3 are positioned washers 5. The bail 3 is adapted to be connected with any suitable form of hook 6, which in turn is connected with a hoisting cable 7.

Ihe body 1 is formed with a tapered bore 8 on the inner peri hery of which are formed circumferential grooves or recesses 9 and 10. The body 1 at the bottom of the recesses 9 is formed tapered downwardly, as illustrated at 11, and is also formed tapered downwardly, as illustrated at 12, at the bottom of the recess 10. The tapered faces 11 and 12 form riding surfaces upon which the complementary tapered faces 13 and 14 of the circumferential flanges 15 and 16 of the slips 17 ride. The body 1 is also formed tapered downwardly at the upper edge of the upper circumferential recess 10, as illustrated at 18, and is so formed at this point that the periphery as shown at 19, extends inwardl beyond the periphery, as shown at 20, of the raised ortion 21 of the body 1 which is intermediate the recesses 9 and 10. The upper circumferential flange 16 is tapered, as shown at 22, complementary to the taper, shown at 18, of the body 1, and the slips 17 are recessed inwardly above the flange 16 to a greater depth than below the annular flange 16, and the inner walls 23 and 24 of the slips 17 above and below the circumferential flange 16 are tapered to corres ond with the taper of the bore 8 of the bo yl. The slips 17 are so formed that the inner bore orpassageway formed between them is substantlally vertical and their inner peripheries are serrated, as illustrated at 25, to provide a gripping surface to grip the casing 26.

Means are provided for mechanically actuating the slips 17 within the body 1, which meansare preferably of the following construction:

Rotatably mounted upon the upper surface 27 of the bod 1 is a cam race block 28. The cam race lock 28 is secured to the body 1 by means of a split ring 29 which is secured to the body 1 and to the block 28, and is secured in position by means of bolts ,30 which pass through eyes 31 formed on one half of the ring 29 and are screwthreaded in the eyes 32 formed in the opposite half of the split ring 29. The split ring 29 is formed at its lower end with an inwardly extending circumferential flange 33 which fits within an annular recess 34 formed in the upper edge of the body 1. The split ring 29 is slidably secured to a rotatable block 28 by means of a circumferential flange 35 which is formed inwardly on the ring 29 and fits within an annular recess 36 formed in the block 28 so as to permit the block 28 to rotate on the body 1. Formed at the upper ends of the slips 17 are cars 37 through the bores 38 of which pins 39 are mounted. Mounted on the pins 39 are cam rollers 40 The cam rollers 4 are ada ted to ride upon cam races 41 formed in the block 28.

Means are rovided for turning the block 28 to cause t e rollers 40 to pass along the cam races 41 and raise or lower the slips 17 to or from the non-operating position, which means preferably comprise a bar 42 which is adapted to be inserted into either one or more ports 43 formed in the block28.

Means are provided for preventing the slips 17 from lateral movement during the rotation of the block 28, which means preferably comprise guide blocks 44 which are inserted between the adjacent edges of the slips 17. The guide blocks 44 are mounted in ta ered key-ways 45 which extend substantlally vertically in the body 1 in the bore 8. The engaging ends of the guide blocks 44 are tapered, as illustrated at 46, to fit within these tapered key-ways. Means are provided for holding the guide blocks 44 in position, which preferably comprise bolts 47 which are screwthreaded' in the body 1 near the upper end and which are passed through washer plates 48 which engzge the upper ends of the guide blocks It will be obvious from the foregoing that when the block 28 is rotated upon the body 1, the slips 17 will be moved upwardly from the position illustrated in Fig. 3 to the position illustrated in Fig. 4 until the flanges 15 and 16 pass into the complementary recesses 9 and 10. The bore of the body 1 being tapered, the slips 17 will move back from engagement with the casing 26 during this upward movement so that the casing 26 will be free to pass through the vertical bore formed on the inner eriphery of the slips 17. When the slips 1 are moved upwardly to occupy the position illustrated in Fig. 4, the tapered sections 18 and 22 of the body 1 and the flange 16, respectively, will prevent accidental dis lacement of the slips 17 and will act to loc or hold the slips in a non-gripping position. When the slips 17 are moved inwardly by rotation of the ring 28, the slips 17 will be guided into osition by the complementary guiding sur aces 11 and 12 of the body 1 as the'correspondingly tapered surfaces 13 and 14 of the slips 17 ri e downwardly during the movement of the block 28.

The inwardly extending portion 19 of the u per flange of the body 1 provides a stop 511011 will engage with the up r surface of the annular flange 16 of the s ip to cause the slips to pass outwardly into the recesses 9 and 10 when the slips have been raised to a. point where the upper flange 16 of the slip en ages the inwar ly extending portion 19. e taper, as illustrated at 18 at this portion of the body 1, rovides a riding surface along which the P8 are caused to ride as the same are pulled further upward by the rotation of the ring 28 on the body 1. The provision of this inwardly extending portion 19 insures a ainst displacement of the slips from the b0 y 1 of the elevator by vertical movement while the pipe 26 is within the central bore of the b0 y 1.

The slips 17 are preferably so formed as to maintain a line of contact between each separate slip and the body 1 of the elevator when the slips are moved inwardly to engage the pipe 26. In order to provide such a line of contact between the slips and the body of the elevator to permit the slips 17 to rock inthe body 1 to equalize for pipe irregularities and also to permit the slips 17 to rock in the body 1 upon the initial impulse imparted to the slip 17 to raise verticall in the body 1 to disengage the pipe 26. n forming the slips 17, the slips are first cast or formed to approximate the same exterior diameter as the interior diameter of the body 1 and the same are then split from the ring casting in which the same are formed to provide the segmental slips 17 which are then mounted upon a mandrel of a diameter less than the inner bore of the pipe sought to original ring from which the slips were formed. Spacers are mounted between the slips on the mandrel to prevent the same moving on the mandrel and the slips are then turned to' an exterior diameter less than the interior diameter of the body 1. As indicated in Fig. 8, when a slip 17 is mounted within the body. 1 in position to engage a pipe, the slip on its rear surface engages the body 1 only at a vertical line passing through the point 50. The line of contact thereby maintained between the segmental slips 17 and the body 1 permits the slips 17 to rock slightly within the body 1 so as to adjust themselves to any pipe irregularities that may be present in the be gripped by the slips 17. The provision of a line contact between the segmental slips and the body 1 is also an important feature in this invention, in that it allows the slips to rock slightly in the body 1 and hence partially disengage them selves from the pipe 26 when the ring 28 is rotated on the body 1 to raise the slips 17 in the body 1 and hence release the pipe.

Having fully described the preferred embodiment of our invention, it is to be understood that the scope of our invention is not limited to the details herein set forth, but is of the scope of the appended claims.

We claim:

1. In a device of the class described, the combination of a body havin a tapered bore therethrough, a plurality o sectional slips mounted in the bore, the sectional slips and body having a plurality of complementary riding and inner engaging surfaces, a block mounted on the body and providing cam ways, a cam roller carried by each of said sectional sli and mounted in the cam ways, and means dr rotating the block.

2. In a device of the class described, the combination of a body having a tapered bore formed therethrough, a lurality of sectional slips mounted in the bore, the body having a plurality of vertically spaced recesses formed outwardly from tie tapered bore, the slips having a corresponding plurality of complementary spaced flanges adapted to fit within and ride in the said recesses, the upper portion of one of said recesses and one of said flanges being formed with complementary tapers to provide holding means to prevent vertical displacement o the slips when the same are expanded to the non-gripping position.

3. In a device of the class described, the combination of a body having a tapered bore therethrough, a plurality of sectional slips mounted within the bore, means secured to the body for holding the slips from rotation relative to the body, the slips and body having a plurality of spaced complementary riding surfaces, a block mounts on the body, means secured to the slips and operatively connected with the block for positively forcing the slips vertically to and from engaging position on rotation of the block relative to the body.

4. In a device of the class described, the combination of a body having a ta ered bore therethrough and a plurality o sectional slips mounted within the bore, the slips and body having a plurality of spaced complementary interengaging riding surfaces, one of which riding surfaces of the slips is provided with an interengaging portion adapted to engage a com lementary interengaging portion of one of the riding surfaces of the body for holding the slips from displacement vertically inwardly o the bore of the body when the slips are moved to the nongripping position, and means for positively forcing the slips vertically within the bore of the body to and from the engaging position.

5. In a device of the class described, the combination of a body having a tapered bore formed therethrough, and having a plurality of riding surfaces, a plurality of sectional slips mounted within the bod means mounted within the body for hol ing the slips from rotation relative to the body, the sectional slips having a plurality of complementary riding and engaging surfaces, one of which complementary riding and engag' ing surfaces of the slips projects inwardly beyond the other of said riding and en gaging surfaces to provide an inclined riding surface operative to engage one of the complementary riding surfaces of the body to draw the slips to expanded position when the slips are moved vertically, and means mounted on the body for positively forcing the slips vertically to and from engaging position.

6. A mechanically operated slip handler, comprising a body having a tapered bore therethrough, and a plurality of slips mounted within the body, the slips and body having complementary interengaging riding surfaces, means for positively forcing the slips vertically within the bore of the body to and from engaging position, and one of the riding surfaces formed on the body being advanced within the bore of the body to engage one of the complementary riding surfaces formed on the slips to move the slips outwardly in the tapered bore of the body away from engaging position as the sli s are moved vertically.

In a device of the class described, the combination of a body having a tapered bore therethrough, a plurality of segmental slips mounted within the bore, the segmental slips and body havin a plurality of comlementary riding an engaging surfaces, a iilock mounted on the body and providing cam ways, a cam roller carried by each of the slips and adapted to ride in the cam ways, means for rotating the block to cause the slips to move vertically in the bore of the body, the said slips having an external diameter at the points of engagement with the body less than the internal diameter of the body at the said points of en agement to provide a line contact between the slips and the body permitting the slips to rock in the body when contracted to engaging position.

8. In a mechanically operated slip handler, the combination of a body having atapered bore, a plurality of sectional sli s mounted in the bore, a block mounted on t 0 body, means secured to the body and the block for rotatably securing the block to the body, the block being provided with cam ways, a cam roller carried by each of said sectional slips mounted in the cam ways, and means for rotating the block to raise and lower said slips in the bore.

9. In a mechanically operated slip handler, the combination of a body having a tapered bore, said body having vertically spaced recesses formed therein a plurality of tapered sectional slips mounted in the bore, the segmental slips having a lurality of eripheral flanges adapted to ti t within sai recesses formed in the body, and a rotatable cam means for positively raising and lowering the sectional slips in the body and cause the slips to ride on' the peripheries of said flanges of the slips intermediate the recesses of the body.

10. In a mechanically operated slip han dler, the combination of ,a body having a tapered here said body having annular recesses formed therein, a plurality of segmental slips mounted in the bore, the segmental slips having curved tapered peripheries, the radii of curvature of which is less than the radii of curvature of the tapered bore of the bod the segmental slips also having a plura it of peripheral flanges adapted to fit wit in said annular recesses formed in the body, and rotatable cam means for positively raising and lowering the segmental slips in the body to cause the slips to ride on the peripheries of said flanges of the slips intermediate the sunn lar recesses of the body.

11. In a mechanically operated slip handler, the combination of a body having a tapered bore, said bodv having vertically spaced recesses formed therein, a pluralitv of tapered sectional slips mounted in the bore, the segmental slips having a plurality of peripheral flanges adapted to fit within said recesses formed in the body, one of said complementary flan es and recesses being formed to provide holding means to revent vertical displacement of the slips w on in the raised position, and rotatable cam means for positively raising and lowering the sectional slips in the body.

12. In a mechanically operated slin handler, the combination of a body having a tapered bore, said bod having a recess formed therein, a plura ity of tapered sectional slips mounted in the bore, the sectional slips having a eripheral flange ada ted to fit within said the ody, there being formed on the periphoral flange and bod complementary ridlng surfaces to draw the slips transversely of the bore when the slips are raised, and means mounted on the body and operatively connected with the slips for positively raising and lowering the slips in the bore.

13. In a mechanically operated sli handler, the combination of a body having a tapered bore, said body having vertically spaced recesses formed therein, a lurality of tapered sectional slips mounte in the bore, the sectional slips having a plurality of com lementary flanges formed thereon, the said complementary flanges and recesses providing riding interengagin means between the slip and body, one 0 which complementary sets of recesses and complementary flanges providing riding surfaces for drawing the sli s transversely of the bore of the body as t e slips are raised vertically in the bore, and means mounted on the body for ositively raising and lowering the slips in tlib bore of the body.

14. In a 'deviceof the class described, the combination of a body having a tapered bore formed therethrough, a plurality of sectional tapered slips mounted in the bore, the body having a plurality of vertically spaced recesses formed outwardly from the tapered bore, the slips having a correspond,- ing plurality of complementary spaced flanges adapted to fit within and ride in recess formed 1n 9 an upwardly flarin said recesses, one of the sets of flanges and recesses being formed with complementary tapers to rovide means for drawing the sectional sips radially outward relative to the bore formed through the body, and for holding the sectional slips from vertical displacement when the slips are expanded to the nonripping position, and means for raising t e slips in the bore of the body. 15. In a device of the class described, the combination of a bod having a tapered bore formed therethroufi the body having a plurality of vertica y spaced recesses formed outwardly from the ta ered bore, a plurality of tapered sectional s ips mounted in the .bore, the slips having a pluralit of complementary spaced flanges adapte to fit within and ride in the said recesses, one set of said recesses and flanges being formed with complementary tapers to provide holding means to prevent vertical displacement of the slips when the same are expanded to the non-gripping position.

16. In a device of the class described, the

combination of a body having a tapered bore formed therethrough, a pluralit of complementary slips mounted in the ore, the body having a downwardly tapering riding surface, the sectional slips having each riding surface and means for raising tie sectional slips vertically in the body so that the said riding surfaces on the sectional slips and body engage as the slips are moved vertical y to draw the sli s outward of the bore formed throu h the body.

17. n a device of the class described the combination of a body having a tapered ore formed therethrough, a pluralit of sectional tapered slips mounted in t e bore, a body having a plurality of vertically spaced recessesformed outwardly from the tapered bore, the slips having a correspondin plurality of complementary spaced anges adapted to fit within and ride in the said recesses, the upper portions of said recesses and flanges being formed with complementary sur aces to provide holding means to prevent vertical displacement of the slips when the same are expanded to the nongrippingposition, and means for positively raising and lowering the slips in the bore of the body.

18. In a device of the class described the combination of a body having a tapered ore formed therethrough, a plurality of sectional slips mounted in g the bore, means mounted in the bore for preventing the slips from rotating in the bore, the b0 y having a plurality of vertically spaced recesses formed outwardly from the tapered bore, the slips having a corresponding lurality of complementary spaced flan es a apted to fit within and ride in the said recesses, one

set of said recesses and flanges being formed with complementary riding surfaces, and means for raising the slips in the bore of the body to cause the riding surfaces to engage and move the slips transversely and outwardly of the bore of the body as the slips are raised.

19. In a device of the class described the combination of a body having a tapered re formed therethrough, a plurality of sectional slips mounted in the bore, the body having a plurality of vertically spaced recesses formed outwardly from the tapered bore, the slips having a correspondi plurality of complementary s accd anges adapted to fit within and ri e in the said recesses, the upper portion of said recesses and flan es being formed with complementary surfaces to provide a holdin means to prevent vertical displacement o the slips when the same are expanded to the non gripping position, and means mounted within the bore for holding the sectional slips from rotating.

20. In a device of the class described, the combination of a body having a tapered bore formed therethrough, a plurality .of sectional slips mounted in the bore, the body and slips having complementary tapered riding surfaces, and means for positively raising and lowering the slips in the bore of the body so that as the slips are raised vertically the complementary riding surfaces enga e to cause the slilps to be moved transverse y outwardly in t e bore.

21. In a mechanically operated slip elevator, the combination of a bod having a tapered bore therethrough, a lurality of tapered sectional slips mounte within the bore, means secured to the body for holding the slips from rotation relative to the body, the slips and body having complementary rlding surfaces, and means for moving the sllps vertically in the body to engage the complementary riding surfaces to cause the slips to move transversely outwardly in the bore as the same are raised.

22. In a device of the class described, the combination of a body having a tapered bore therethrough, a plurality of tapered sectional slips mounted in the bore, the sectional slips and body having a plurality of complementary riding and tapered enga ing surfaces, a block mounted on the b0 y and providing cam ways, a cam roller carried by each of said sectional slips and mounted'in a cam way, each ofsaid cam ways being provided with a horizontal portion, and means for rotating the block on the body until the cam rollers are engaged in the horizontal portions of the cam ways.

23. In a device of the class described, the combination of a body having a tapered bore formed therethrough, a plurality of sectional slips mounted in the bore, the sectional slips and body having complementary tapered ridin surfaces, blocks mounted in ways forme intermediate the slips, means for removably securing the blocks in position, and means for raising and lowering 5 the slips in the bore of the bod 24. In a device of the class escribed, the combinationof a body having a tapered bore formed therethrough, a plurality of tapered 'sectional slips mounted in the bore, the sec- 10 tional slips and body having a plurality of complementary riding surfaces, a block mounted on the body and providing cam ways, a split ring rotatably securing the block to the body, the s lit ring bein pro vided with upper and ower inward y extending circumferential flanges fitting within annular recesses formed in the block and body respectively, a cam roller carried by each of the sectional slips and mounted in a cam way, and means for rotating the block.

25. In a device of the class described, the combination of a bod having a tapered bore therethrough, a p urality of segmental slips mounted within the bore, means for holding the slips from rotation in the bore relative to the body, means operatively secured to the body and connected with the slips for raising the slips in the bore, the slips having an external diameter at points of their engagement with the body less than the internal diameter of the body at said points of engagement with the slips to provide a line contact between the slips and the bod so that as said raising means ,isactuate the slips are rocked on said line of contact to break the line of contact and permit the slips to be raised in the bore of the body from engaging position to non-engaging position, the segmental slips in the body having complementary riding and engaging surfaces formed so that as the slips are raised vertically the said complementary riding and engaging surfaces enga to draw the slips outwardly in the bore'o the body.

26. In amechanically. operated slip handler, the combination of a body having a tapered bore, a plurality, of tapered segmental slips mounted within the bore, the slips being mounted within the bore of the body to provide a line contact between the periphery of the slips and thebody when the slips are set, means operably connected with the body and slips and adapted to be actuated to provide a force having! vertical and horizontal components operating to rock the sli s to break the line contact between the sips and the body, and to raise the slips in the bore of the body, and means formed in the bore of the body normally out of engagement with the slips and adapted to engage the slips when theslips are raised to move the slips outwardly from the bore of the body.

27. In a tube grip ing device, the combinations of a. housing aving a tapered open- "tapered faces, said slips having eac said slips having u ing formed therethrough, a projection formed inwardly and above said tapering opening the lower or under face of said projection forming a downwardly tapering riding surface, a plurality of sllps mounted in said housing, means to raise said slips, said slips having each a complementary taper to seat in the tapered opening of said housing, said slips having each an upwardly facin and flaring riding surface so that the ri ing surfaces on the slips and housing engage as the slips are moved vertically upward to draw the sli s radially outward of the opening formed t rough the housing.

28. In a tube gripping device, the combination of a housing having a plurality of axiall aligned tapered openings providing slip engaging faces, a recess formed outwardly and lntermediately of two slip engagin faces, a projection formed inwardly and a ove said tapered opening, a recess formed outwardly and intermediately of the upper tapered opening and the inward formed projection, the upper wall of said recess forming a. downwardly tapered riding surface, a plurality of slips mounted in sald housing, means to raise said slips, said slips having a plurality of spaced complementary tapered faces to engage the slip engaging faces in said housing In the tube gripping position, an inwardly formed recess 1n each of said slips between the s aced an upwardly, facing and flaring riding surface so that. the riding surfaces on the slips and housing engage as the slips are. moved vertically upward to draw the slips radially outward into the recesses formed in the housin 29. n a device of the character described a housing having upper and lower tapered openin s providing slip on aging faces, a recess ormed outwardly an intermediately of said tapered openin s, the upper face of said recess forming a ownwardly tapered riding surface, a plurality of slips mounted in sald housing, means to raise said sli s,

er and lower comp ementary tapered portions adapted to seat on the slip engaging faces in said housing when the slips are in the grippin position, said slips having each an outwar y projection intermediate the upper and lower ta ered portions forming an upwardl flaring riding surface so that the said ri ing surfaces on the slips and housing engage as the slips are moved vertically upward to draw the slips radiall outward of the opening formed through the housing.

30. In a device of the class described, a housing having a plurality of axially aligned tapered openings providing slip engaging faces, a recess formed outwardly and intermediately of two axially spaced slip engaging faces, the upper face of said recess forming a downwardly tapered riding surface, a plurality of slips mounted in said housing with means to raise said slips, said slips having a plurality of complementary tapered portions adapted to seat on the slip engaging faces in said housing when the slips are in the gripping position, a recess formed in each of said slips having an axial length greater than the upper adjacent slip engaging face on said housing, a projection formed on each of said slips below said recess, and forming an upwardly flaring riding surface between them so that the said riding surfaces on the slips and housing engage as the slips are moved vertically upward to rapidly retract the slips radially outward of the opening and into the interlocking recesses formed in the housing and slips.

31. A mechanically operated slip handler comprising a body having a tapered bore therethrough, and a plurality of slips mounted within the body, the slips and body having complementary interen aging riding surfaces, and one of the riding surfaces formed on the body being advanced within the bore of the body to engage one of the complementary riding surfaces formed on the slips to move the slips outwardly in the tapered bore of the body away from .engaging position as the slips move vertically upward.

Signed at Torrance, Calif., this 22 day of March 1927.

FORREST J. YOUNG. JOSEPH A. DUNN.

CERTIFICATE OF CORRECTION.

, Patent No. 1,909,601.

May 16, 1933.

FORREST J. YOUNG, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

"segmental" read "sectional"; and that with these corrections therein that the 82, claims 9 and 11, respectively, for

the said Letters Patent should be read Page 4, lines 52 and same may conform to the record of the case in the Patent Office.

Signed and sealed this 8th day of August, A. D. 1933.

(Seal) M. J. Moore.

Acting Commissioner of Patents.

forming a downwardly tapered riding surface, a plurality of slips mounted in said housing with means to raise said slips, said slips having a plurality of complementary tapered portions adapted to seat on the slip engaging faces in said housing when the slips are in the gripping position, a recess formed in each of said slips having an axial length greater than the upper adjacent slip engaging face on said housing, a projection formed on each of said slips below said recess, and forming an upwardly flaring riding surface between them so that the said riding surfaces on the slips and housing engage as the slips are moved vertically upward to rapidly retract the slips radially outward of the opening and into the interlocking recesses formed in the housing and slips.

31. A mechanically operated slip handler comprising a body having a tapered bore therethrough, and a plurality of slips mounted within the body, the slips and body having complementary interen aging riding surfaces, and one of the riding surfaces formed on the body being advanced within the bore of the body to engage one of the complementary riding surfaces formed on the slips to move the slips outwardly in the tapered bore of the body away from .engaging position as the slips move vertically upward.

Signed at Torrance, Calif., this 22 day of March 1927.

FORREST J. YOUNG. JOSEPH A. DUNN.

CERTIFICATE OF CORRECTION.

, Patent No. 1,909,601.

May 16, 1933.

FORREST J. YOUNG, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

"segmental" read "sectional"; and that with these corrections therein that the 82, claims 9 and 11, respectively, for

the said Letters Patent should be read Page 4, lines 52 and same may conform to the record of the case in the Patent Office.

Signed and sealed this 8th day of August, A. D. 1933.

(Seal) M. J. Moore.

Acting Commissioner of Patents. 

